Re: design advice on predicate name

From:

Marco Maggi

Subject:

Re: design advice on predicate name

Date:

Sun, 20 Aug 2006 08:29:08 +0200

"Neil Jerram" wrote:
>My intuition is that the NAN? name should be used only
>for a procedure which takes a single number and reports
>whether it is NAN or not (as #t/#f).
Yes. The abstract behind having a NAN? for my custom
vectors and matrices is to let the user write math
functions that work for both numbers and composite
numeric objects. To let him try them out. I am not sure
about how significant it is, though.
"Neil Jerram" wrote:
>Is it a feature of Octave that any predicate can
>automatically map over a vector, or can `isnan' only
>be applied to a vector?
Predicates that act upon numbers can be applied to
numbers, vectors and matrices. And they always work
like MAP-NAN? Using the number/vector/matrix oriented
functions of Octave it is possible to write custom
predicates that behave in the same way.
Octave also has 'all()' and 'any()' which return a single
0/1 result if all or any of the elements of a num/vec/mat
is 0 or 1. So Octave requires two functions call to
achieve the result of HIT-NAN?
--
Marco Maggi
"They say jump!, you say how high?"
Rage Against the Machine - "Bullet in the Head"